Semiautomatic starting mechanism



July 23, 1935.

M. P. WHITNEY SEMIAUTOMATIC STARTING MECHANI SM Filed April 29, 1935 3743' 44 41 19 21 1 M 1 SM MA -gm [N VENTOR TORNEY M mm? Patented July 23,1935 UNITED STATES PATENT OFFICE SEMIAUTOMATIC STARTING MECHANISMApplication April 29,

9 Claims.

This invention relates to a semi-automatic starting mechanism forinternal combustion engines and more particularly to a controlling relayfor a starting system so arranged that manipu1ation of a manual switchsuch as the ignition switch of the engine initiates the crankingoperation, the cranking being automatically interrupted when the enginestarts, and the starting system being maintained inoperative until theignition switch is opened and reclosed.

It is an object of the present invention to provide a semi-automaticstarting mechanism of the above type which is efiicient and reliablewhile simple and economical in construction.

It is another object to provide such a device which is independent ofany running function of the engine for its operation.

It is a further object to provide such a device which uses a function ofthe starting motor to cause disconnection of the starting mechanism whenthe engine starts.

It is another object to provide such a device which is easily installedby means of simple wiring connections.

Further objects and advantages will be apparent from the followingdescription in conjunction with the accompanying drawing in which:

Fig. 1 is a semi-diagrammatic View showing in perspective a preferredembodiment of the invention, the parts being shown in normal or idleposition and some thereof being cut away for the sake of clarity;

Fig, 2 is a similar View showing the parts in the positions assumedduring the cranking operation; and

Fig. 3 is a similar View showing the parts in the positions assumedduring the self-operation of the engine.

Referring first to Fig. 1 of the drawing, there is illustrated astarting system for an internal combustion engine, not shown, includinga battery l, grounded at 2 and connected by a lead 3 to a startercontrolling device including a magnetic starting switch, indicatedgenerally by numeral 4, the starting switch being connected by a lead 5to a starting motor SM which is grounded at t to complete the startingcircuit.

A control circuit for the magnetic starting switch is providedcomprising the battery I, lead 3, a manual switch "I which is preferablythe ignition switch for the engine, lead 8 and electromagnet 9. Thecontrol circuit is normally completed from electromagnet 9 through leadI l contact l2, contact I 3 normally in engagement therewith,

1933, Serial No. 668,583

and swinging armature l4 carrying the contact it, which armature isgrounded to complete the control circuit as indicated at 15.

An alternative ground connection for the electromagnet 9 is provided inthe form of a lead 16 5 which is grounded indicated at IT through anelement 22% having sufhcient resistance to substantially weaken theelectromagnet 9 when the contacts l2, [3 are open.

The starting switch 4 comprises stationary con- 1:) tact members 19 and22 and a bridging conductor 22 mounted on a rod 23 traversing theelectromagnet $9 and provided at its upper end with an armature 2arranged to cooperate with a U -shaped field member 25 and a centralpole piece which are magnetized by the electromagnet 9. The bridgingelement 22 of the switch is mounted for limited sliding movement on thelower end of the rod 23 against the compression of a spring 21 wherebythe armature 24 is permitted to engage the pole 26 and field 25 by aslight additional movement after the switch element 22 has engaged thecontacts [9, 2!.

Contacts 52, 13 are arranged to be normally closed so as to causeenergization of electromagnet 9 when the ignition switch '3 is closed,but according to the present invention, means are provided for causingthe contacts to be opened when the en ine starts and to be held open aslong as the operator-controlled ignition switch 1 remains an closed.This is accomplished by providing means actuated by the closing of thestarting switch for displacing the contacts l2, l3 in unison to causethem to be tensioned toward open position, means for holding saidcontacts together in displaced position during the cranking operation,which means releases the contacts when the engine starts, and means forholding the contact I2 in displaced position as long as the ignitionswitch is closed, whereby the release of the contact l3 when the enginestarts causes the contacts to open and remain open.

The means for displacing the contacts l2, l3 as here shown comprises anactuating element in the form of a bar 28 attached at its upper end tothe armature 24 as indicated at 29 and arranged to slide through a guideopening 3! in a frame member 32. The lower end of the bar 28 carries atriangular shaped cam 33 arranged to engage with a pin 34 projectingfrom the pivoted armature M. The cam member 33 is approximately in theform of a right triangle the side forming the hypotenuse of which isarranged as illustrated in Fig. l to move the pin 34 in a direction toswing the armature 14 toward the starting switch 4 when the bar 28 ismoved downward by the main armature 2d. The altitude of the righttriangle is slightly less than the total travel of the bar 28 wherebywhen the armature 2t is in its fully closed position, the cam 33 haspassed slightly below the pin 34, as shown in Fig. 2, leaving thearmature I l free to return to idle position.

The means for holding the contacts l2, H3 in displaced positioncomprises an L-shaped member of magnetic material, one arm 5% or" whichis arranged to contact the frame plate 32 which is also of magneticmaterial and the other arm of which forms the support 3? for theswinging armature it. The member 35 thus traverses the U-shaped loopformed by the elements i9, 22, 2| of the starting switch and isaccordingly magnetized by cranking current traversing said switchelements. A fixed pole piece for the armature it is provided as hereillustrated by bending down a tongue 33 from the frame plate 32 intoclose proximity to the upper end of the armature it, means such as anon-magnetic adjusting screw 39 being preferably provided for regulatingthe minimum air gap between the armature and pole piece and therebyregulating the retaining force exerted by the cranking current.Adjustable yielding means in the form of a spring ii is provided fornormally hold ng the armature it against a suitable back stop 42.

In order that the contact l2 may be normally retained in engagement withthe contact l3 and may be moved by said contact it when the armature Mis displaced, the contact i2 is mounted on a spring strip 53 insulatedfrom the member 35. The means for retaining the contact 22 in displacedposition comprises a small auxiliary armature #34 yieldably retained ina recess in the main. armature 2 1 as by means ofv guides 35 andcompression springs ii). A rod l? is suitably attachedto an extendedportion of said armature 44 as indicated at 43, and is arranged to slidethrough an opening 49 in the frame plate 32 into proximity with the end5i of the spring strip 33. The end 5! of said strip is preferably bentat right angles in order to provide vertical resiliency, and the'end ofthe rod 3? is notched as shown more particularly at 52 in Fig. 2 toengage and retain the end of the spring strip when theiarmature 4G is inits lower position. The springs 46 are made so delicate that thearmature t isretained in its lower position by a very slight amount ofmagnetism in the electromagnet 9, whereas a spring 53 is provided fornormally retaining the armature 2 1 in open position, which spring is ofsufficient strength to cause the opening of the starting switch inresponse to the reduction in the strength of electromagnet 9 caused bythe insertion of the resistance I8 in its control circuit.

In the operation of this device and starting with the parts in thepositions shown in Fig. 1, closure of the ignition switch completes thecircuit from the battery 5 through leads 3 and 8 to electromagnet sandfrom thence through lead ll, contacts i2 and E3 to the ground at 15. Theconsequent energization of electromagnet 9 attracts armatures Z i'and til causing the bridging member 22 to engage the main switch contacts l9,2!, while the bar 28 causes cam 33 to swing armature i i inwardly anddisplace contacts 12, it'while' the lower end of rod il slides into thereturn path of the end 5! of. spring strip 53. As soon as the startingswitch 4 is closed, cranking 'is initiated and a heavy current traversesthe elements as, 22, '21 or the switch, causing the magnetization of themagnetic circuit formed by elements i i, 31, 3t, 32 and 38 whereby thearmature M is retained in its inner position although the cam 33 haspassed below the rod 36. This is the cranking position or" the parts asillustrated in Fig. 2. When the engine starts, the reduction in thecurrent traversing the starting circuit due to the release of thecranking load causes the flux between the pole piece 38 and armature isto be reduced sufficiently to permit spring ll to swing the armature itback to its idle position. At this time, however, the contact i2 isprevented from following the contact l3 by reason of the latchingengagement of the rod ll with the end of the spring strip wherebycontacts i2, it are opened.

Opening contacts l2, l3 break the direct ground connection of theelectromagnet 9 whereby it is connected to the ground only by lead itand resistance E8. Resistance E8 causes the electromagnet 9 to be soweakened as to release the main armature 24 which is moved to idleposition by the spring 53, thereby opening the starting switch.Auxiliary armature lid, however, is retained by the weak magnetizationof electromagnet 9 whereby contacts i2, iii are held open during theself-operation of the engine as illustrated in Fig. 3. When the engineis stopped by the opening of ignition switch it, the electromagnet 9 iscompletely deenergized and the auxiliary armature 5 i permitted toreturn to its idle position as illustrated in Fig. 1 under the action ofsprings 46.

Although but one form or" the invention has been shown and described indetail, it will be understood that other embodiments are possible andthat various changes may be made in the details or" construction andarrangements of the parts without departing from the spirit of theinvention as defined in the claims appended hereto.

What is claimed is:

1. In a starter controlling device, a magnetic starting switch includinga movable armature, a control circuit therefor including normally closedswitch means, means connected to be moved by said armature fortensioning said switch means toward open position, means responsive tocrank ing current for holding said switch means closed during crankingbut arranged to allow said switch means to open when the cranking loadis relieved and means under the control of the operator for holding saidswitch means open.

2. In a starter controlling device, a magnetic starting switch, acontrol circuit therefor including normally closed contacts and a manualswitch, means actuated by the closing movement of the starting switchfor biasing said contacts to openposition, means energized by thecranking current for holding said contacts closed during cranking, andmeans directly under the control of said manual switch for locking saidcontacts open.

'3. In a semi-automatic starter control for internal combustion engines,a starting circuit including astarting switch, a control circuittherefor including a manual switch and make and break means, meanswhereby closure of the starting switch displaces the elements of themake and break device in unison and holds one only thereof in displacedposition, and means responsive to cranking current for holding saidelements in displaced position.

4. In a semi-automatic starter control for in ternal combustion engines,a starting circuit including a starting switch, a control circuit therefor including a manual switch and make and break means, means wherebyclosure of the starting switch displaces the elements of the make andbreak device in unison and holds one only thereof in displaced position,means responsive to cranking current for holding said elements indisplaced position, and means including said manual switch forcontrolling said first holding means.

5. In a semi-automatic starter control for internal combustion engines,a starting switch, a set of yieldably mounted control contacts, meansactuated by closure of the starting switch for displacing said contactsin unison and means responsive to the relief of the cranking load forreleasing one only of said contacts.

6. In a semiautomatic starter control for internal combustion engines, astarting switch, a set of yieldably mounted control contacts, meansactuated by closure of the starting switch for displacing said contactsin unison, means responsive to cranking current for holding saidcontacts displaced, and means under the control of the operator forholding one only of said contacts in displaced position.

7. A semi-automatic starting system for internal combustion enginesincluding a magnetic starting switch having main switch contacts andcontrol contacts, a main armature for controlling the main contacts,means operated by said main armature for displacing the control contactsin unison, an auxiliary armature and means operated by said auxiliaryarmature for holding one only of said control contacts in displacedposition.

8. A semi-automatic starting system for internal combustion enginesincluding a magnetic starting switch having main switch contacts andcontrol contacts, a main armature for controlling the main contacts,means operated by said main armature for displacing the control contactsin unison, means responsive to cranking current for holding the controlcontacts displaced, an auxiliary armature, and means operated by saidauxiliary armature for holding one only of said control contacts indisplaced position.

9. A semi-automatic starting system for internal combustion enginesincluding a magnetic starting switch having main switch contacts andcontrol contacts, a main armature for controlling the main contacts,means operated by said main armature for displacing the control contactsin unison, an auxiliary armature and means operated by said auxiliaryarmature for holding one only of said control contacts in displacedposition, and means under the control of the operator for controllingsaid auxiliary armature.

MAURICE P. WHITNEY.

